/*
 * PythonTokenMarker.java - Python token marker
 * Copyright (C) 1999 Jonathan Revusky
 * Copyright (C) 1998, 1999 Slava Pestov
 *
 * You may use and modify this package for any purpose. Redistribution is
 * permitted, in both source and binary form, provided that this notice
 * remains intact in all source distributions of this package.
 */

package org.syntax.jedit.tokenmarker;

import javax.swing.text.Segment;

import org.syntax.jedit.KeywordMap;
import org.syntax.jedit.SyntaxUtilities;

/**
 * Python token marker.
 * 
 * @author Jonathan Revusky
 * @version $Id: PythonTokenMarker.java,v 1.3 1999/12/14 04:20:35 sp Exp $
 */
public class PythonTokenMarker extends TokenMarker
{
    private static final byte TRIPLEQUOTE1 = Token.INTERNAL_FIRST;

    private static final byte TRIPLEQUOTE2 = Token.INTERNAL_LAST;

    public PythonTokenMarker()
    {
        this.keywords = getKeywords();
    }

    public byte markTokensImpl(byte token, Segment line, int lineIndex)
    {
        char[] array = line.array;
        int offset = line.offset;
        lastOffset = offset;
        lastKeyword = offset;
        int length = line.count + offset;
        boolean backslash = false;

        loop: for (int i = offset; i < length; i++)
        {
            int i1 = (i + 1);

            char c = array[i];
            if (c == '\\')
            {
                backslash = !backslash;
                continue;
            }

            switch (token)
            {
            case Token.NULL:
                switch (c)
                {
                case '#':
                    if (backslash)
                        backslash = false;
                    else
                    {
                        doKeyword(line, i, c);
                        addToken(i - lastOffset, token);
                        addToken(length - i, Token.COMMENT1);
                        lastOffset = lastKeyword = length;
                        break loop;
                    }
                    break;
                case '"':
                    doKeyword(line, i, c);
                    if (backslash)
                        backslash = false;
                    else
                    {
                        addToken(i - lastOffset, token);
                        if (SyntaxUtilities.regionMatches(false, line, i1, "\"\""))
                        {
                            token = TRIPLEQUOTE1;
                        }
                        else
                        {
                            token = Token.LITERAL1;
                        }
                        lastOffset = lastKeyword = i;
                    }
                    break;
                case '\'':
                    doKeyword(line, i, c);
                    if (backslash)
                        backslash = false;
                    else
                    {
                        addToken(i - lastOffset, token);
                        if (SyntaxUtilities.regionMatches(false, line, i1, "''"))
                        {
                            token = TRIPLEQUOTE2;
                        }
                        else
                        {
                            token = Token.LITERAL2;
                        }
                        lastOffset = lastKeyword = i;
                    }
                    break;
                default:
                    backslash = false;
                    if (!Character.isLetterOrDigit(c) && c != '_')
                        doKeyword(line, i, c);
                    break;
                }
                break;
            case Token.LITERAL1:
                if (backslash)
                    backslash = false;
                else if (c == '"')
                {
                    addToken(i1 - lastOffset, token);
                    token = Token.NULL;
                    lastOffset = lastKeyword = i1;
                }
                break;
            case Token.LITERAL2:
                if (backslash)
                    backslash = false;
                else if (c == '\'')
                {
                    addToken(i1 - lastOffset, Token.LITERAL1);
                    token = Token.NULL;
                    lastOffset = lastKeyword = i1;
                }
                break;
            case TRIPLEQUOTE1:
                if (backslash)
                    backslash = false;
                else if (SyntaxUtilities.regionMatches(false, line, i, "\"\"\""))
                {
                    addToken((i += 4) - lastOffset, Token.LITERAL1);
                    token = Token.NULL;
                    lastOffset = lastKeyword = i;
                }
                break;
            case TRIPLEQUOTE2:
                if (backslash)
                    backslash = false;
                else if (SyntaxUtilities.regionMatches(false, line, i, "'''"))
                {
                    addToken((i += 4) - lastOffset, Token.LITERAL1);
                    token = Token.NULL;
                    lastOffset = lastKeyword = i;
                }
                break;
            default:
                throw new InternalError("Invalid state: " + token);
            }
        }

        switch (token)
        {
        case TRIPLEQUOTE1:
        case TRIPLEQUOTE2:
            addToken(length - lastOffset, Token.LITERAL1);
            break;
        case Token.NULL:
            doKeyword(line, length, '\0');
        default:
            addToken(length - lastOffset, token);
            break;
        }

        return token;
    }

    public static KeywordMap getKeywords()
    {
        if (pyKeywords == null)
        {
            pyKeywords = new KeywordMap(false);
            pyKeywords.add("and", Token.KEYWORD3);
            pyKeywords.add("not", Token.KEYWORD3);
            pyKeywords.add("or", Token.KEYWORD3);
            pyKeywords.add("if", Token.KEYWORD1);
            pyKeywords.add("for", Token.KEYWORD1);
            pyKeywords.add("assert", Token.KEYWORD1);
            pyKeywords.add("break", Token.KEYWORD1);
            pyKeywords.add("continue", Token.KEYWORD1);
            pyKeywords.add("elif", Token.KEYWORD1);
            pyKeywords.add("else", Token.KEYWORD1);
            pyKeywords.add("except", Token.KEYWORD1);
            pyKeywords.add("exec", Token.KEYWORD1);
            pyKeywords.add("finally", Token.KEYWORD1);
            pyKeywords.add("raise", Token.KEYWORD1);
            pyKeywords.add("return", Token.KEYWORD1);
            pyKeywords.add("try", Token.KEYWORD1);
            pyKeywords.add("while", Token.KEYWORD1);
            pyKeywords.add("def", Token.KEYWORD2);
            pyKeywords.add("class", Token.KEYWORD2);
            pyKeywords.add("del", Token.KEYWORD2);
            pyKeywords.add("from", Token.KEYWORD2);
            pyKeywords.add("global", Token.KEYWORD2);
            pyKeywords.add("import", Token.KEYWORD2);
            pyKeywords.add("in", Token.KEYWORD2);
            pyKeywords.add("is", Token.KEYWORD2);
            pyKeywords.add("lambda", Token.KEYWORD2);
            pyKeywords.add("pass", Token.KEYWORD2);
            pyKeywords.add("print", Token.KEYWORD2);
        }
        return pyKeywords;
    }

    // private members
    private static KeywordMap pyKeywords;

    private KeywordMap keywords;

    private int lastOffset;

    private int lastKeyword;

    private boolean doKeyword(Segment line, int i, char c)
    {
        int i1 = i + 1;

        int len = i - lastKeyword;
        byte id = keywords.lookup(line, lastKeyword, len);
        if (id != Token.NULL)
        {
            if (lastKeyword != lastOffset)
                addToken(lastKeyword - lastOffset, Token.NULL);
            addToken(len, id);
            lastOffset = i;
        }
        lastKeyword = i1;
        return false;
    }
}
